The final command will prompt you for a password. Don't type one. Just
press the return key. Though this seems like a big security hole, it's not as
bad as it looks; the uucp user does not have a password in
/etc/passwd, so anyone who can run programs as that user must
already have an account on the client with fairly good permissions.

This step generates an SSH v2 DSA key set; the id_dsa.pub public
key file will come in handy later.

Congratulations! You have finished the client side of the
configuration.

###### this is the UUCP 'sys' file for Taylor UUCP #######
# client
system client
time any
port tcp
protocol t
remote-send /var/spool/uucppublic
remote-receive /var/spool/uucppublic
# other clients use the same lines

Out of paranoia, I recommend to tell UUCP that the directory for
remote-send and remote-receive is
/var/spool/uucppublic.

Create a file called /etc/uucp/passwd, containing:

###### this is the UUCP 'passwd' file for Taylor UUCP #######
yourlogin yourpassword

That's all of the server-side UUCP configuration.

Server SSH Configuration

The final server step is its SSH configuration. Switch to the UUCP user by
doing su -m uucp, then create the authorized_keys
file:

$ touch /var/spool/uucp/.ssh/authorized_keys

Copy the content of the client's id_dsa.pub file (located in
/var/spool/uucp/.ssh/) into
/var/spool/uucp/.ssh/authorized_keys on the server. To assuage SSH's
paranoid permissions check, perform the following command:

chmod go-rwx && chown uucp:uucp

Edit the authorized_keys file with the editor of your choice and
insert this before its content:

Be aware that the DSA key should all fit on one long line; there must be no
carriage return.

Once you have done the above, do cd /var/spool/ && chmod go-w
uucp. This should make SSH less paranoid about these file
permissions.

Congratulations. You have finished the server configuration.

Final Tweaks and Testing

The end is in sight. Now register the DSA key from with the client's SSH
/var/spool/uucp/.ssh/known_hosts file. You only need to do this
once.

Switch to the UUCP user (su -m uucp), then connect to the
server with ssh -v uucp@server.domain.tld. Answer "yes" when SSH
asks you if you want to add the DSA public key of the server to your list of
known and trusted hosts.

At this point, all incoming mail destined for hosted-domain.tld will end up
spooled and stored in the /var/spool/uucp/client directory of the
server. UUCP will gladly send it to the client whenever it calls in through
the SSH tunnel.

If this does not work for you, then you forgot something along the way.
Check again your Postfix configuration and UUCP configuration on either or both
the client and the server.

Going Live

You can now test your setup from the client.

Dial-up your Internet provider using PPP if you need to. Skip this step if
you have a permanent link to the Internet.

Do su -m uucp followed by /usr/libexec/uucp/uucico -f
-sserver. To see mail flowing in, type uulog -f -sserver.
If you need to watch what happens to the email after Postfix receives it, check
the Postfix log file with tail -f /var/lo/maillog.

Now fire up your email client (Mozilla mail, Thunderbird, sylpheed, nmh,
emacs, etc.) and send some mail. You should now also see it being
spooled in the UUCP queue (uustat -sserver) and waiting to be sent
out to the server next time you launch uucico.

Note that you can use uustat -k <jobid> on the client
or the server to kill any job(s) seen by using uusat -s
<system>. You'll see something like:

Type uustat -k system.NI8whUuAALf1 to remove this job from the
UUCP queue before it is sent out.

I encourage anyone who wants to have a deeper understanding of all of the
possibilities of UUCP to read the info file info UUCP or the PDF
file for Taylor UUCP, which is an invaluable source of information.

Now the final touch: if you want to launch this automatically and you have a
permanent Internet connection, add a cron job to /var/cron/tabs/uucp.
As root, do crontab -u uucp -e and insert the content below,
modifying the parameters as you wish. This example polls the UUCP server every
five minutes:

Final Words

I hope you enjoyed this little tutorial and that you can put UUCP to work
for your own usage. I would like to find out how many people in the world are
using UUCP, so please send me email if you are, so that I can
compile a list of countries and a number of users.